I'd be looking for a seized hinge or roller. More likely a hinge point, a seized roller would probably still slide. Disconnect from the door opener trolley, put penetrating oil not WD-40 in EVERY hinge point and roller and try it again tomorrow. Look very closely at every hinge for fine metallic powder indicating corrosion.

I'm guessing the door could be methodically bent back into shape.

Be careful working around the door springs.

Good luck!!!

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